jms, if you want to learn about collars, the best book I can recommend is "Collars" at the Random Walk Trading Thanks You website.

They also have a tag along service where by you can watch them trade collars every day. It's a great education, BUT it is on the US stock markets.

I trade/invest in the US and I have a 3 month subscription to the collars tag along service. It is very very good.

Most complete education on the strategy you will find in the world I think.

Cheers
The Stig

PS, the covered call has unlimited risk and limited return. If the stock tanks too far you have yourself a buy and hold strategy LOL

You can still screw up collars and loss money. There is no free money in the markets.